1. Field of the Invention
The present invention relates to a wheel balance weight. In particular, it relates to a wheel balance weight which is installed to an inner peripheral surface of a rim in a wheel of a vehicle.
2. Description of the Related Art
In a wheel-assembled state; namely: in a state where a tire of an automobile, or the like, is assembled with a wheel, there arises a drawback in that, as the unbalance enlarges in the peripheral direction around the rotary shaft of the wheel assembly as well as in the direction of the rotary shaft of the wheel assembly, the vibrations, noises, and the like, generate when driving a vehicle.
The vibrations, noises, and so on, result from the unbalance in the wheel. Accordingly, the wheel is equipped with a wheel balance weight, which can cancel the unbalance. The installation position of the wheel balance weight to the wheel and the mass of the wheel balance weight are determined by measuring the unbalance of the wheel assembly with a special purpose measuring apparatus.
As one of the conventional wheel balance weights, there has been, for example, a wheel balance weight, which is installed to an inner peripheral surface of a rim in the wheel by bonding a substantially plate-shaped weight, having a predetermined mass, by means of an adhesive tape, etc.
When the conventional wheel balance weight is manufactured, the weight is formed as a flat plate shape. When it is installed to the wheel, the weight is curved along the inner peripheral surface of the rim in the wheel. Moreover, since the curvature of the conventional wheel balance weight depends on the curvature of the wheels to which it is installed, it is determined appropriately.
In the conventional wheel balance weight, the weight has been formed of lead, which is one of soft materials. The weight, which is formed of lead, can be readily processed, and can be readily curved with a manual labor.
However, it has been known that lead put a large load onto environment when it is abolished. Consequently, ferrous alloys, which put a less load onto environment, have come to be employed as a material for the weight.
Yet, a wheel balance weight, which uses a weight being formed of a ferrous alloy, suffers from a problem in that it requires an enormous force when it is installed to a wheel.
Specifically, when such a wheel balance weight is installed at a predetermined position in a wheel, it is necessary to curve the weight, which is formed of a ferrous alloy. However, since such a weight exhibits a high hardness, it has been necessary to exert a great force to curve it.
Hence, in order that such a weight can be curved with a gentle force, another wheel balance weight has been devised which has a weight with a groove formed in the top surface. Here, the xe2x80x9ctop surfacexe2x80x9d refers to a surface of the weight onto which no double-sided tape adheres, and which faces the axis of a wheel when the wheel balance weight is installed to the wheel.
In such a wheel balance weight, the weight has a less thickness at the portion in which the groove is formed than at the other portions in which no groove is formed. Accordingly, when a stress is given to the weight to curve it, the given stress concentrates at the portion in which the groove is formed. As a result, the weight can be curved with a minor force.
However, when the weight is bent excessively, the conventional wheel balance weight, which uses the weight with the groove formed in the top surface, suffers from a problem in that the weight fractures at the groove.
Moreover, in such a conventional wheel balance weight as well, it has been required to reduce the force needed for curving the weight when it is installed to a wheel.
When the weight with the groove formed in the top surface is bent, the weight is compressed on the top surface side and is extended on the bottom surface side. Since ferrous alloys, which are used in the weight, exhibit a low malleability, it is necessary to exert a large force in order that the weight is fully extended on the bottom surface side. Thus, it has been needed to lessen the enormous force.
The present invention has been developed in view of the aforementioned circumstances. It is therefore an object of the present invention to provide a wheel balance weight, which can be readily installed to a wheel.
In order to carry out the object, the inventors of the present invention repeatedly investigated the ways for curving weights of wheel balance weights with ease. As a result, they found out that it was possible to achieve the object by making a weight with a groove formed in a bottom surface thereof. Thus, they completed the present invention.
For example, a wheel balance weight according to the present invention is characterized in that it comprises: a weight being formed as a substantially strip shape, being made from a ferrous alloy, having opposite top and bottom surfaces and at least a groove, the groove being formed in the bottom surface of the weight and crossing in the width-wise direction thereof being substantially perpendicularly to the longitudinal direction thereof; and a double-sided tape having opposite adhesive surfaces, being disposed back to back with each other, one of the opposite adhesive surfaces to be bonded onto the bottom surface of the weight, the other one of the opposite adhesive surfaces to be bonded onto an inner peripheral surface of a wheel.
In the present wheel balance weight, since the groove is formed in the bottom surface of the weight, it is possible to curve the weight with a less force. Hence, it is possible to install the present wheel balance weight to a wheel with ease.
A process according to the present invention is adapted for manufacturing the present wheel balance weight, and is characterized in that it comprises the steps of: forming a weight being formed as a substantially strip shape, being made from a ferrous alloy and having opposite surfaces; forming a groove in one of the opposite surfaces of the resulting weight by pressing the one of the opposite surfaces thereof with a punch, the groove crossing in the width-wise direction of the weight being substantially perpendicularly to the longitudinal direction thereof, wherein a plastic deformation at opposite ends of the weight in the width-wise direction thereof is less than a plastic deformation at a central portion of the weight in the width-wise direction thereof; and applying a double-sided tape, having opposite adhesive surfaces, to the weight so as to adhere one of the opposite adhesive surfaces onto the one of the opposite surfaces of the weight with the groove formed therein.
In accordance with the present process for manufacturing the present wheel balance weight, it is possible to inhibit burrs, flashes, and the like, from protruding at the ends of the groove when the punch is pressed onto the one of the opposite surfaces of the weight in order to form the groove. Hence, it is possible to manually handle the present wheel balance weight, which has been manufactured by the present manufacturing process, safely.